Title: Walker_Category::start_el Published: April 25, 2014 Last modified: April 28, 2025 --- # Walker_Category::start_el( string $output, WP_Term $data_object, int $depth, array $args = array(), int $current_object_id ) ## In this article * [Description](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#description) - [See also](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#see-also) * [Parameters](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#parameters) * [Source](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#source) * [Hooks](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#hooks) * [Related](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#related) * [Changelog](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#changelog) [ Back to top](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#wp--skip-link--target) Starts the element output. ## 󠀁[Description](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#description)󠁿 ### 󠀁[See also](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#see-also)󠁿 * [Walker::start_el()](https://developer.wordpress.org/reference/classes/Walker/start_el/) ## 󠀁[Parameters](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#parameters)󠁿 `$output`stringrequired Used to append additional content (passed by reference). `$data_object`[WP_Term](https://developer.wordpress.org/reference/classes/wp_term/) required Category data object. `$depth`intoptional Depth of category in reference to parents. Default 0. `$args`arrayoptional An array of arguments. See [wp_list_categories()](https://developer.wordpress.org/reference/functions/wp_list_categories/). More Arguments from wp_list_categories( … $args ) Array or string of arguments. See [WP_Term_Query::__construct()](https://developer.wordpress.org/reference/classes/wp_term_query/__construct/) for information on accepted arguments. Default:`array()` `$current_object_id`intoptional ID of the current category. Default 0. ## 󠀁[Source](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#source)󠁿 ```php public function start_el( &$output, $data_object, $depth = 0, $args = array(), $current_object_id = 0 ) { // Restores the more descriptive, specific name for use within this method. $category = $data_object; /** This filter is documented in wp-includes/category-template.php */ $cat_name = apply_filters( 'list_cats', esc_attr( $category->name ), $category ); // Don't generate an element if the category name is empty. if ( '' === $cat_name ) { return; } $atts = array(); $atts['href'] = get_term_link( $category ); if ( $args['use_desc_for_title'] && ! empty( $category->description ) ) { /** * Filters the category description for display. * * @since 1.2.0 * * @param string $description Category description. * @param WP_Term $category Category object. */ $atts['title'] = strip_tags( apply_filters( 'category_description', $category->description, $category ) ); } /** * Filters the HTML attributes applied to a category list item's anchor element. * * @since 5.2.0 * * @param array $atts { * The HTML attributes applied to the list item's `` element, empty strings are ignored. * * @type string $href The href attribute. * @type string $title The title attribute. * } * @param WP_Term $category Term data object. * @param int $depth Depth of category, used for padding. * @param array $args An array of arguments. * @param int $current_object_id ID of the current category. */ $atts = apply_filters( 'category_list_link_attributes', $atts, $category, $depth, $args, $current_object_id ); $attributes = ''; foreach ( $atts as $attr => $value ) { if ( is_scalar( $value ) && '' !== $value && false !== $value ) { $value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value ); $attributes .= ' ' . $attr . '="' . $value . '"'; } } $link = sprintf( '%s', $attributes, $cat_name ); if ( ! empty( $args['feed_image'] ) || ! empty( $args['feed'] ) ) { $link .= ' '; if ( empty( $args['feed_image'] ) ) { $link .= '('; } $link .= ''; } $link .= ''; if ( empty( $args['feed_image'] ) ) { $link .= ')'; } } if ( ! empty( $args['show_count'] ) ) { $link .= ' (' . number_format_i18n( $category->count ) . ')'; } if ( 'list' === $args['style'] ) { $output .= "\tterm_id, ); if ( ! empty( $args['current_category'] ) ) { // 'current_category' can be an array, so we use `get_terms()`. $_current_terms = get_terms( array( 'taxonomy' => $category->taxonomy, 'include' => $args['current_category'], 'hide_empty' => false, ) ); foreach ( $_current_terms as $_current_term ) { if ( $category->term_id === $_current_term->term_id ) { $css_classes[] = 'current-cat'; $link = str_replace( 'term_id === $_current_term->parent ) { $css_classes[] = 'current-cat-parent'; } while ( $_current_term->parent ) { if ( $category->term_id === $_current_term->parent ) { $css_classes[] = 'current-cat-ancestor'; break; } $_current_term = get_term( $_current_term->parent, $category->taxonomy ); } } } /** * Filters the list of CSS classes to include with each category in the list. * * @since 4.2.0 * * @see wp_list_categories() * * @param string[] $css_classes An array of CSS classes to be applied to each list item. * @param WP_Term $category Category data object. * @param int $depth Depth of page, used for padding. * @param array $args An array of wp_list_categories() arguments. */ $css_classes = implode( ' ', apply_filters( 'category_css_class', $css_classes, $category, $depth, $args ) ); $css_classes = $css_classes ? ' class="' . esc_attr( $css_classes ) . '"' : ''; $output .= $css_classes; $output .= ">$link\n"; } elseif ( isset( $args['separator'] ) ) { $output .= "\t$link" . $args['separator'] . "\n"; } else { $output .= "\t$link
\n"; } } ``` [View all references](https://developer.wordpress.org/reference/files/wp-includes/class-walker-category.php/) [View on Trac](https://core.trac.wordpress.org/browser/tags/6.9.4/src/wp-includes/class-walker-category.php#L101) [View on GitHub](https://github.com/WordPress/wordpress-develop/blob/6.9.4/src/wp-includes/class-walker-category.php#L101-L255) ## 󠀁[Hooks](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#hooks)󠁿 [apply_filters( ‘category_css_class’, string[] $css_classes, WP_Term $category, int $depth, array $args )](https://developer.wordpress.org/reference/hooks/category_css_class/) Filters the list of CSS classes to include with each category in the list. [apply_filters( ‘category_description’, string $description, WP_Term $category )](https://developer.wordpress.org/reference/hooks/category_description/) Filters the category description for display. [apply_filters( ‘category_list_link_attributes’, array $atts, WP_Term $category, int $depth, array $args, int $current_object_id )](https://developer.wordpress.org/reference/hooks/category_list_link_attributes/) Filters the HTML attributes applied to a category list item’s anchor element. [apply_filters( ‘list_cats’, string $element, WP_Term|null $category )](https://developer.wordpress.org/reference/hooks/list_cats/) Filters a taxonomy drop-down display element. ## 󠀁[Related](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#related)󠁿 | Uses | Description | | [get_term_link()](https://developer.wordpress.org/reference/functions/get_term_link/)`wp-includes/taxonomy.php` | Generates a permalink for a taxonomy term archive. | | [get_terms()](https://developer.wordpress.org/reference/functions/get_terms/)`wp-includes/taxonomy.php` | Retrieves the terms in a given taxonomy or list of taxonomies. | | [get_term_feed_link()](https://developer.wordpress.org/reference/functions/get_term_feed_link/)`wp-includes/link-template.php` | Retrieves the feed link for a term. | | [__()](https://developer.wordpress.org/reference/functions/__/)`wp-includes/l10n.php` | Retrieves the translation of $text. | | [esc_attr()](https://developer.wordpress.org/reference/functions/esc_attr/)`wp-includes/formatting.php` | Escaping for HTML attributes. | | [esc_url()](https://developer.wordpress.org/reference/functions/esc_url/)`wp-includes/formatting.php` | Checks and cleans a URL. | | [number_format_i18n()](https://developer.wordpress.org/reference/functions/number_format_i18n/)`wp-includes/functions.php` | Converts float number to format based on the locale. | | [get_term()](https://developer.wordpress.org/reference/functions/get_term/)`wp-includes/taxonomy.php` | Gets all term data from database by term ID. | | [apply_filters()](https://developer.wordpress.org/reference/functions/apply_filters/)`wp-includes/plugin.php` | Calls the callback functions that have been added to a filter hook. | [Show 6 more](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#) [Show less](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#) ## 󠀁[Changelog](https://developer.wordpress.org/reference/classes/walker_category/start_el/?output_format=md#changelog)󠁿 | Version | Description | | [5.9.0](https://developer.wordpress.org/reference/since/5.9.0/) | Renamed `$category` to `$data_object` and `$id` to `$current_object_id` to match parent class for PHP 8 named parameter support. | | [2.1.0](https://developer.wordpress.org/reference/since/2.1.0/) | Introduced. | ## User Contributed Notes You must [log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fdeveloper.wordpress.org%2Freference%2Fclasses%2Fwalker_category%2Fstart_el%2F) before being able to contribute a note or feedback.